lkaufman wrote:Mike S. wrote:[quote="mclane & Stockfish.
Maybe my explanation is even more simple but true: Rybka, Ippo & Co are simply better.
The weaker engines just benefit from the
bigger draw rates at big depths/long time controls.
This might be a factor for Houdini, but certainly Ivanhoe (Ippo), Rybka, and all other Ippo-related programs are not stronger than Komodo and not measurably stronger than SF except at bullet chess, so this cannot be the explanation here.
There seem to be two theories to explain the observed scaling behavior:
1. Komodo (and perhaps also SF) are more intelligent but slower, and that this tradeoff usually (but not always) favors the fast programs in blitz and the smart programs at long time controls.
2. For whatever reason, the search in Komodo (and perhaps SF) scales better than the search in the Rybka/Ippo family.
Both could be true. If the second is true, can anyone suggest WHY SF might scale better in search than Ivanhoe et al?
I don't think ''intelligence'' is the right word. There are two different approaches to the search in my view.
Ippo family engines have a search for which they find tactical moves in a very short time.
I think it is a question of search (and evaluation). Like humans. Some humans search mainly for tactical moves.
I'm not a programmer but i think it depends by the evaluation that an engine gives to each move that it analyses.
In this way it could happen that all the moves that don't give a ''break'' in the evaluation are discarded or analysed less time (and perhaps they are good positional moves).
If this would be true, it is logical that these engines find more often and more quickly tactical moves.
On the other hand Komodo plays mainly positionally.
Komodo often manouevres his pieces and pawns for many moves without playing any tactical move.
Probably it depends by the fact that Komodo gives a special evaluation on some moves that lead to some positional patterns.
I mean, probably during the search, Komodo seems to make the opposite of the engines of the ippo family.
Then Komodo analyzes more the ''positional moves'' (probably because it consider them better than other moves with its evaluation) and gives less time or discards some tactical moves.
In fact, sometimes Komodo overlooks some tactical moves, and it depends by the search or sometimes by the evaluation.
If all i wrote would be true, it is logical that in very fast time control, ippo family engines excel.
With more time to think, a positional engine like Komodo has 2 advantages:
1. What Komodo overlooks or evaluates bad in a few seconds can be seen well with more time available.
2.The weight of positional play of Komodo increases a lot and becomes more important than its (relative) weakness in tactics.
Generally speaking i think that the strenght of Komodo is that it plays nice positional and logical moves. It seems that it uses the search just to verify that everything is ok.
On the other hand the strenght of ippo family engines is the approach of the search (i think built mainly for tactical moves) and the evaluation that allows them to find sometimes tactical moves apparently hidden.
In long time control, especially in very long time control, tactics ability is almost useless because the opponent (if he has a good search and evaluation) has all the time to see it.
So the thing that has more importance is the positional/strategical sensibility.
Best Regards
